General purpose EPROM (erasable programmable read only memory) programming apparatus are well known, but are typically sophisticated devices which require a trained engineer or computer programmer to operate. After an EPROM has been programmed by such a device and is on site in the field, only limited servicing or modification of the EPROM and the program stored therein is typically possible on site, and then only by trained service personnel. The same is true for other programmable memory devices which store a computer program, which are generally referred to as firmware. Examples of such other memory devices include EEPROMS (electrically erasable programmable read-only memory devices) and PALs (programmable array logic devices).
Typically, when there is an error in, or other problem with, the firmware, or if the firmware is to be modified or updated, the standard procedure is to send a trained engineer from a central site or origin of the firmware to the remote site of the firmware. If the problem cannot be solved on site or if a replacement EPROM will not solve the problem, the EPROM must be removed and taken back to the central site, along with the relevant information concerning the problem. Even if the EPROM problem can be corrected at that point, however, such a method of program correction or repair is expensive and time consuming and usually results in loss of customer goodwill.